Such a transceiver is used for data transmissions in IrDA applications, For data transmission by means of an optical point-to-point transmission route, the IrDA (Infrared Data Association) standard has been developed. For example, integrated transceiver components known by the designation TFDS 3000 or TFDS 6000 are available from TEMIC TELEFUNKEN microelectronic GmbH, which components correspond to the IrDA standard.
Conventionally there are arranged in a common transceiver housing an infrared transmitter (emitter), an infrared receiver (detector), and an integrated circuit for signal processing. A surface of the transceiver component carries two lens-shaped moldings located adjacent to each other, in whose focal points the transmitter and the receiver are respectively located. These optical lens-shaped moldings are necessary in order to achieve the directional signal emission of the transmitter and the directional sensitivity of the receiver as required by the IrDA standard.
Conventional transceivers have the disadvantage that due to the transmitter and the receiver being located adjacent to each other, they each require their own respective optical system in order to be able to achieve the required directional signal transmission of the transmitter and the directional sensitivity of the receiver. This duplication causes high material costs and the dimensions of the transceiver are relatively large.
If the integrated circuit, the receiver, and the transmitter are arranged in a stack, that is, the receiver on the integrated circuit and the transmitter on the receiver, there is a disadvantage in that a part of the receiver element is covered by the transmitter element, thus reducing the receiver sensitivity. Furthermore, due to the way circuit, receiver, and transmitter are arranged, it is not possible--as, for example is possible with light-emitting diodes (LED)--to arrange the transmitter within a cup-shaped reflector; which, due to the undirected radiation, will cause a reduction in transmission power.